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arXiv · 1511.08969

Cosmic Censorship in Lorentz Violating Theories of Gravity

Michael Meiers·Mehdi Saravani·Niayesh Afshordi
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Abstract

Is Cosmic Censorship special to General Relativity, or can it survive a violation of equivalence principle? Recent studies have shown that singularities in Lorentz violating Einstein-Aether (or Horava-Lifhsitz) theories can lie behind a universal horizon in simple black hole spacetimes. Even infinitely fast signals cannot escape these universal horizons. We extend this result, for an incompressible aether, to 3+1d dynamical or spinning spacetimes which possess inner killing horizons, and show that a universal horizon always forms in between the outer and (would-be) inner horizons. This finding suggests a notion of Cosmic Censorship, given that geometry in these theories never evolves beyond the universal horizon (avoiding potentially singular inner killing horizons). A surprising result is that there are 3 distinct possible stationary universal horizons for a spinning black hole, only one of which matches the dynamical spherical solution. This motivates dynamical studies of collapse in Einstein-Aether theories beyond spherical symmetry, which may reveal instabilities around the spherical solution.

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Michael Meiers, Mehdi Saravani, Niayesh Afshordi. 2015-11-29. Cosmic Censorship in Lorentz Violating Theories of Gravity. https://doi.org/10.1103/physrevd.93.104008

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